Know the Symptoms
During any warm-weather workout or event, watch for the following symptoms:
- Disorientation
- Confusion
- Headache
- Muscle weakness
- Nausea and vomiting
These same symptoms are often attributed to dehydration and heat illness. The misdiagnosis of dehydration when hyponatremia exists can be especially dangerous if more fluids are given to try to reverse dehydration. Avoid this complication and do the math with a doctor or medical professional if you believe you have drunk too much water.
More: 4 Common Hydration Myths
Hydrating Safely for Performance
While fluid is important for normal body function and athletic performance, just how much you need remains a subject of debate. A recent meta-analysis of studies looking at the impact of dehydration on exercise performance found that a reduction of body weight by 2.2 percent or less was not associated with a decrease in performance. This would equate to about 3.5 pounds for a 160-pound athlete.
Also note that the average sweat rate is about 27.4 to 47.3 ounces per hour (one pound of sweat translates to about 15.4 ounces of fluid) while running. Therefore, it would take a 160-pound athlete 1 to 2 hours of no fluid replacement to reach just a 2.2 percent reduction in body weight.
More: How to Hydrate Before, During and After a Workout
The most appropriate recommendation for athletes may be to drink in response to thirst. Learn how to tune into your ability to recognize thirst. Then practice taking in different forms of fluid during training to be prepared for race day. Consider weighing yourself before and after a couple of training workouts. If you're losing more than 1 to 2 pounds per hour, you may not be hydrating enough. If you're gaining weight during each individual training session, you're likely overhydrating.
Many races have frequent water stops, but that doesn't mean you need to replenish fluids every time you see one. Avoid overhydration by going in with a hydration plan. In this plan include:
- location of water stops
- fluids that will be available
- how much you need depending on your thirst, sweat rate, and amount of time you predict you will be out on the course.
Know the signs of overhydration, leave for your race with a hydration plan, and enjoy a long summer of warm runs and sunshine.
More: 10 Race-Day Preparation Tips
Learn more about proper hydration.
